Idea Transcript
FREDERICK COUNTY, MARYLAND STAFF REPORT CONCURRENCE FORM
Ode: Au ~st22,2016
To: Office of the County Executive
Through (Name of Div. Dir.): -------------------------f'--:~--- From (Name & Division): Phone#:
Kevin Demosky, Director, Div of Utilities & Solid Waste Mc@i
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(301) 600-2963 or x12997
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Staff Report Topic:
Request for Public Hearing for Frederick County Design Manual for Water and Sewer Facilities County Funds Requested/Required? Yes _ _ $ _ _ _ _ _ _ _ __
g::!. s:ro
No _:f__
W&S Enterprise Funds
Action Requested: Information Only
Approval _ _./ __
Requires County Executive's:
Signature _ _ __
**• Please remember to flag all pages that need to be executed by the County Executive:"*
Staff Report Review: This staff report has been thoroughly reviewed first by the appropriate divisions/agencies noted on Page 2 followed by those outlined below: Initials
Comments Y/N (Page 2)
2£
IZJ Budget Office [2J Finance Division
lZJ County Attorney's Office Refer to County Council?
Ji_
[{] Chief Administrati\le Officer
Approval to forward to Council?
For Office Use Only Council Meeting Date: - - - - - - - - Public Hearing?
Yes _ _ __
Page 1of2
Presenter: - - - - - - - - - - - - - - -
No _ _ __
Requires Council President's Signature?
Yes _ _ __
'
No _ _ __
June 2016
Other Reviewing Divisions/Agencies: (Click to place a check mark in tl1e following appropriate spaces.) Initials
Date
Comments YIN (noted below)
Initials
Date
Comments YIN (noted below)
Animal Control Citizens Services Emergency Management Fire & Rescue Services Health Services Human Resources lnteragency Information Technologies Office of Economic Development Parks & Recreation Planning & Permitting Public Works Transit Services Utilities & Solid Waste Management Volunteer Fire & Rescue Services Other: Other: Other:
Elected Officials or lndeQendent Agencies:
Board of Education Board of Elections Board of License Commissioners Frederick Community College Frederick County Public Libraries Internal Audit Sheriffs Office Social Services State's Attorney's Office
Comments : 1. From:
Date:
3. From:
4. From:
Page 2 o f 2
June 2016
Jan H. Gardner
FREDERICK COUNTY GOVJSRNMENT DIVISION OF UTILITIES & SOLID WASTE MANAGEMENT
County Executive Kevin L. De111osky, Director
MEMORANDUM TO:
Jan H. Gardner, County Executive
FROM: Kevin L. De1?,~\k7 Director, Division of Utilities and Solid Waste Management (DUSWM~-y'j) DATE:
August 22, 2016
RE:
Proposed Changes to the Frederick County Design Manual for Water and Sewer Facilities; Request to Conduct a Public Hearing
ISSUE: Should the Cow1ty Executive approve taking changes to the Frederick Cou11ty Desig11 Mn11unl for Water n11rf Sewer Facilities ("Design Manual") through the public h earing process? BACKGROUND: DUSWM originally adopted the Design Manual on March 15, 1994 (effective April 1, 1994). 1 The last amendment to the Design Manual addressed the provision for residential sprinkler systems and was adopted effective July 20, 2006.2 Based on DUSWM's Deparbnent of Engineering and Plaiming's ("DoEP") experience, along with feedback from the engineering community, the Design Manual requires revisions and needed to be updated. Initially, this updating effort was started in conjunction with other DUSWM documents. DUSWM initiated an effort to revise their core documents in 2012. They consisted of the following: 1. Standard Details for Water Mains, Sanita1y Sewers and Related Sh·uctures ("Standard Details") 2. General Conditions and Standard Specifications for Water Mains, Sanitary Sewers and Related Structures ("Standard Specifications") 3. Design Manual for Water and Sewer Facilities The Standard Details were revised and adopted January 24, 2013.3 Efforts to revise the Standard Specifications, along with the Design Guidelines, was initiated in 2014. Focus was shifted to have revisions to the Standard Specifications take precedence, which was adopted following a public hearing on November 6, 2014 (effective January 1, 2015).4 Initial comments regarding the Design Manual were received during the public hearing for the Standard Specifications. Since this effort to revise and update the Design Manual was reinitiated in 2015, DoEP received more crm:unents ooth mfernally and externally. A public ouh"each meeting was held on February 29, 2o'fbt()discuss proposed changes and to receive additional comments (a copy of the attendees signin sheet is attached). Prior to the oun·each meeting the proposed changes to the Design Manual and comment b"acking sheet were posted to DUSWM's webpage. As a result of the ouh"each meeting,
3
Resolu tion 94-07. Resolution 06-30. Resolution 13-01. Resolution 14-31.
Frederick Cou11(1•: Rich History, Brig/it Future 4520 Metropolitan Court, Frederick, MD 2 1704 • 301-600-2997
www.FrederickCountyMD.gov
Jan H. Gardner, County Executive RE: Proposed Changes to the Frederick County Design Manual for Water and Sewer Facilities; Request to Conduct a Public Hearing August 22, 2016 Page 2
additional rev1s10ns w ere made and both documents were again posted on April 7, 2016. A notification email was also sent to interested parties, which included the Frederick County Builders Association (Denise Jacoby), the Land Use Council (Jolm Mazelon), other engineering consultants and developers, advising of the posted revisions on April 11, 2016 (a copy is attached). The webpage posting specifically states that a public hearing is pla1med regarding the revisions to the document:
Contn20% without involving Department Head in the discussion. Must show Sewer Drop Service Connections (SDSC) to raise c/o invert at esmt line to max 12.0' or for slopes greater than 5%. Monitoring manhole (std dtl #201.7) to have no drop. Invert in=invert out. (S0121) Monitoring Manhole - Slope of pipe entering to be 1%-2%. (S0118) Sewer mains at manholes with different diameter pipes shall match crown of pipe elevations. (S0114) Junction manholes appearing on multiple profiles must show the same inverts and rim elevation. All SHC pipes connecting into new manholes must have the same invert. (S0107) No manhole drops allowed for pipes greater than 15"diameter. (S0099) Vent tops to be min 1' above 100 yr floodplain and be protected from flood debris and vandalism. Vents are required a min of every 1500' when "WT" manholes are utilized consecutively. ALL sewer service drop connections must be called out and identified. Slopes of 10% or more - the applicable holes shall conform to that slope angle to within 5 degrees. Force mains that discharge into a transition manhole are from a rising grade. (PS0233) For non-metallic force mains an insulated #8 AWG trace wire shall be furnished. (PS0238) Inside drop connections are an approved option. Age of manhole/location of steps crucial. 112
If an inside drop connection is proposed, the plans must include std dtl #202.1 AND the installation 2 or more inside drop connections must use a 72" manhole. If a drop connection is proposed to an existing manhole, field verify that the inside steps and MH joints do not conflict with the connection. Edge of cored hole must be minimum of 9" from joint.
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APPENDIX C (Design Tables, Curves, Forms, etc.) TABLE OF CONENTS
Table of Contents......................................
C-123
Water Storage Requirements............................. C-124 Fire Hydrant Design Flow Rates......................... C-125 Depth of Cover and Mannings "n" ......................C-126 Flow Factors...........................................
C-119
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WATER STORAGE REQUIREMENTS The DUSWM will evaluate water storage requirements based on but not limited to the following items: 1. 2. 3.
Projected water demands (average, maximum, fire, etc.) Integration with the existing system Water aging analysis
DUSWM will work with the engineer of record regarding necessary calculations and modeling as required for the given scenario.
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FIRE HYDRANT DESIGN FLOW RATES USE FLOW RATE (gpm) ________________________________________________________________________ Residential (one and two-family)
1,000
Residential (multi-family)
1,250
Commercial
1,500
Industrial
1,500
Educational/Institutional 1,500 ________________________________________________________________________
Notes: 1. Flow rates are to be accommodated while maintaining a minimum residual pressure of 20 psi at the highest point in the supplying system. 2. Fire flow rate are to be combined with maximum daily rates of flow in the distribution network 3. Storage tanks in the system shall be considered at their minimum elevation (elevation at which tank calls for water) when determining the fire flow residual pressure. 4. These flow rates are to be used in the design of public water mains, whether developer or County funded. The use of a property may require a higher flow rate that is to be accommodated by onsite (private) storage/pumping systems.
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DEPTH OF COVER AND MANNING’S “n”
Type of Pipe
Minimum Structural Cover (feet)
Mannings "n"
PVC (Sewer)
3.5
0.009
Ductile Iron
2
0.012
Ductile Iron (cement lined)
2
0.013
Ductile Iron (epoxy lined)
2
0.011
Reinforced Concrete
3
0.013
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Type of Development
FLOW FACTORS
(FF)
Dwelling Unit, detached
# Units
x 350 = gpd
Townhouses
# Units
x 300 = gpd
Apartments, multi family
# Units
x 300 = gpd
Apartments, elderly
# Units
x 200 = gpd
Mobile Homes
# Units
x 175 = gpd
Office Buildings
Gross Sq. Ft. x 0.20 = gpd
Medical Office Buildings
Gross Sq. Ft. x 0.175 = gpd
Warehouses
Gross Sq. Ft. x 0.021 = gpd
Retail Stores
Gross Sq. Ft. x 0.048 = gpd
Supermarkets
Gross Sq. Ft. x 0.20 = gpd
Drug Stores
Gross Sq. Ft. x 0.13 = gpd
Beauty Salons
Gross Sq. Ft. x 0.35 = gpd
Department Store with Lunch Counter
Gross Sq. Ft. x 0.08 = gpd
Department Store without Lunch Counter
Gross Sq. Ft. x 0.04 = gpd
Banks
Gross Sq. Ft. x 0.044 = gpd
Restaurants
# Seats
Service Stations
Gross Sq. Ft. x 0.18 = gpd
Laundries and Cleaners
Gross Sq. Ft. x 0.31 = gpd
Laundromats
Gross Sq. Ft. x 3.68 = gpd
Car Wash (without Recycle)
Gross Sq. Ft. x 4.90 = gpd
Hotels
Gross Sq. Ft. x 0.256 = gpd
Motels
Gross Sq. Ft. x 0.224 = gpd
Hospitals
# Beds
x 346 = gpd
Theaters
# Seats
x 1
Nursing Homes
# Beds
x 130 = gpd
Dry Goods Stores
Gross Sq. Ft. x 0.048 = gpd
Shopping Centers
Gross Sq. Ft. x 0.172 = gpd
Auto Dealership
Gross Sq. Ft. x 0.078 = gpd
Barber Shop
Gross Sq. Ft. x 0.20 = gpd
Carry out (Except Major Chains)
Gross Sq. Ft. x 0.20 = gpd
Carry out (Chain)
# Seats
Church
# Sanctuary Seats x 4 = gpd
Garage (Auto/Truck Repair)
Gross Sq. Ft. x 0.014 = gpd
Library
Gross Sq. Ft. x 0.10 = gpd
Bakery
Gross Sq. Ft. x 0.15 = gpd
Racket Club/Tennis Club
# Courts
Pool (with Hot Showers)
# Members
x 24.2 = gpd
= gpd
x 10 = gpd
x 300 = gpd x 6
= gpd
Pool (without Hot Showers) # Members x 4 = gpd ====================================================================== 118
Flow factors are for planning purposes only. Flow factors include inflow/infiltration. Actual capacity charge will be determined at the time of application for building permit. Use of these flow factors shall not be used in lieu of actual fixture counts (as defined in the DUSWM Rules and Regulations) to determine capacity charges or any other fees.
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Flow Factors (Continued) Zoning
Design Flow Uses
(GPD)
R-1 R-3 R-5
General:
100/person
R-8
Single Family:
370/d.u.
R-12
Townhouse:
300/d.u.
R-16
Apartment:
300/d.u.
VC
General:
2000/acre
GC
Motel:
130/unit
HS
Office: 30/employee or whichever greater
0.20/net sq. ft.
GI
General:
7500/acre
MM
Warehouse:
750/acre
ORI
Other: Varies with Industry
PUD MH
LI
School General: 16/person =================================================================== Flow factors are for planning purposes only. Flow factors include inflow/infiltration. Actual capacity charge will be determined at the time of application for building permit. Use of these flow factors shall not be used in lieu of actual fixture counts (as defined in the DUSWM Rules and Regulations) to determine capacity charges or any other fees.
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REFERENCES American Society of Civil Engineers and Water Pollution Control Federation, Design and Construction of Sanitary and Storm Sewers, 1969. Sanks, Tchoboanoglous, Bosserman, Jones, Puming Station Design, 2006 Anne Arundel Department of Public Works, Anne Arundel County Design Manual, January 2001. Baltimore County Department of Public Works, Baltimore County Design Manual, January 17, 1983. Howard County Department of Public Works, Howard County Design Manual Volume II Water and Sewer, October 1980 and amendments through October 1990. Loudon County Sanitation Authority, Sewer System – Standards and Extensions, April 13, 1979. Washington Suburban Sanitary Commission, WSSC Design Manual, March 1983. Hydraulic Institute, Standards for Centrifugal, Rotary and Reciprocating Pumps, 14th Edition (1983). American Society of Mechanical Engineers, Centrifugal Pumps – Performance Test Codes, 1973. Frederick County Codes, include:
Building Code of Frederick County BOCA National Building Code Frederick County Plumbing Code National Electric Code NFPA Life Safety Code Maryland Building Code for the Handicapped
Code of Maryland Regulations (COMAR) A Report of the Committee of the Great Lakes – Upper Mississippi River Board of State Sanitary Engineers, Recommended Standards for Sewage Works, 1978. A Report of the Committee of the Great Lakes – Upper Mississippi River Board of State Health and Environmental Managers, Recommended Standards for Water Works, 1987.
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